Evaluation of Organoleptic, pH and Pasting Properties of Blends from Unripe Plantain, Soybean and Ginger

Abstract

Aim: To evaluate the organoleptic, pH and pasting properties of unripe plantain (Musa paradisiaca), soybeans (Glycine max) and ginger (Zingerber officianale) as edible sources of food which can be processed into flour for several purposes. Methodology: The plant materials (unripe plantain, soybean and ginger) used in this study were processed separately into flours. The flours were then formulated into different proportions  i.e. composite flour blends; A (100%), B(80:14:6)%, C(70:26:4)%, D (60:38:2)% and E(50:50)% and analyzed for pasting properties, pH and sensory properties using  standard procedures for 12weeks. Data generated were subjected to one-way analysis of Variance (ANOVA) in randomized block to test significant variations (P<0.05) among mean values obtained. Results: The results showed that the peak viscosity of the blends which is the ability of starch to swell freely before their physical breakdown ranged from 651 RVU to 2766 RVU. The highest value (2766 RVU) was recorded in blend A, follow by B (1916 RVU), C (1383 RVU), D (972 RVU) while the lowest value (651 RVU) was recorded in E. The highest trough value (2462 RVU) was recorded in blend A and followed by B (1687 RVU), C (1224 RVU), D (875 RVU) and the lowest was E (550 RVU). This implies that the higher the quantity of soybean substituted, the lesser the trough. Trough which measures the ability of paste to withstand breakdown during cooling was significantly different (P<0.05) in the blends. There were significant differences (P<0.05) in the aroma of the various blends at week 0. Blend B with 6% ginger inclusion had the highest score (8.83) at 0 week, followed by blend C (8.50) with 4% ginger. Blends A and E without ginger inclusion had the lowest scores (6.25 and 6.75 respectively) at 12 weeks. The highest pH blend E (6.98) was observed at 12 weeks storage. The pH of the various blends remained acidic throughout storage of 12 weeks, an indication of shelf stability of products. Conclusion: It was evident that supplementing unripe plantain flour adequately improved the pasting properties, pH and organoleptic properties which is a useful application in pastries like cakes and other snacks